A chainsaw consists of a metal chain with teeth that are part of the chain. The chain is guided around a rigid part of the chainsaw that forms a blade enabling the teeth to rove wood as it rotates. The chain is driven around the blade by a motor. The rigid part that the chain moves around is called the bar and the size of the bar will determine the type of work the chainsaw is most suited to and the safety considerations that need to be borne in mind when using selecting it.